The early pockets of ice have prompted one Chicago cruise line to cancel its New Year's Eve fireworks cruise for the first time in five years. The company that manages harbors on the lakefront has started efforts to protect their docks from ice. And in the northern part of Lake Michigan, the Coast Guard has been busy breaking through ice, making sure shipping crews can make their scheduled deliveries.
As of Monday, more than 13 percent of Lake Michigan was covered by ice, compared with its icelessness this time last year, said George Leshkevich, a physical scientist at the National Oceanic and Atmospheric Administration Great Lakes Environmental Research Laboratory. Over the past five years, the average ice coverage on Lake Michigan around this time of year was closer to 2 percent, according to laboratory data.
In fact, it was not until Jan. 22 this year that ice cover compared with the amount on the lake now. The laboratory predicts that up to 62 percent of the Great Lakes will be frozen over this winter, above the long-term average of 55 percent.
"With this cold spell we've been having, ice we find has been forming earlier on the lakes than ... the past few years," Leshkevich said. "(Forecasts) are indicating a season with a little bit above normal ice cover."
In Chicago, Shoreline Sightseeing had to refund about 70 tickets for its New Year's Eve lake event, largely because the boats they would have used are small open-air vessels, tough for sightseers, said Amy Hartnett, Shoreline's director of sales and marketing.
While boats have been moved out of lakefront harbors since mid-November, there is work that must be done now to minimize damage to docks due to more than a foot of ice, said Scott Stevenson, vice president of Westrec Marinas, the company that manages Chicago's harbors. A Chicago Park District-owned tugboat, The Commissioner, runs up and down the channels in Burnham Harbor to break the ice and keep it from building up too much pressure on the docks. Other harbors have underwater tube systems around the docs that blow compressed air bubbles to break down the ice.
"We've found that by breaking up the ice, we have less damage," Stevenson said. "When ice moves around, it can be damaging."
The ice forming around Chicago pales in comparison with the problems that the Coast Guard has been battling farther north. In the upper Great Lakes, ice-cutting operations are making way for commercial vessels in and out of the Port of Green Bay, said Chief Petty Officer Alan Haraf of the Coast Guard's public affairs office.
The Coast Guard's annual operation to retrieve buoys and other navigational aids that would be damaged under the ice, usually between October and late December, was also more complicated this year because of the early freeze, said Petty Officer 3rd Class Christopher Yaw, a spokesman out of the Coast Guard's Cleveland office.
Clearing a path through the ice is vital for the U.S. shipping industry, which can move 20 percent of its annual total cargo during the ice season, or about 16 million to 18 million tons, said Glen Nekvasil, vice president of the Lake Carriers' Association, a trade group. Every year, 25 million to 35 million tons of iron ore are shipped to the lower end of Lake Michigan, particularly to the Indiana steel mills in Gary, Indiana Harbor and Burns Harbor.
The ice is getting formidable, particularly in the lower St. Mary's River, which connects Lake Superior to the lower Great Lakes.
"Most of the iron ore and the biggest coal shipping ports are on Lake Superior, so if our ships can't get through the St. Mary's River, the steel mills won't get their iron ore and power plants won't get their coal," Nekvasil said.
Two Coast Guard icebreakers as well as one from Canada are working on the river,
Nekvasil said.
"This is shaping up to be a very tough winter," he said. "We have had a number of mild winters recently, and one of our concerns has been that the crews on the icebreakers, with mild winters, they do not get the experience that they need.
"But they're doing a good job," Nekvasil said." image above, "Ice abounds in Lake Michigan, as viewed from Northerly Island on Tuesday. (Nancy Stone, Chicago Tribune / December 17, 2013). via Free Rep.
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